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All IPCC definitions taken from Climate Change 2007: The Physical Science Basis. Working Group I Contribution to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change, Annex I, Glossary, pp. 941-954. Cambridge University Press.

Posted on 12 December 2009 by John Cook

Throughout the Climategate controversy, the second most cited email is from climate scientist and IPCC lead author Kevin Trenberth. The highlighted quote is this: "The fact is that we can't account for the lack of warming at the moment and it is a travesty that we can't." This has been most commonly interpreted (among skeptics) as climate scientists secretly admitting amongst themselves that global warming really has stopped. Is this what Trenberth is saying? If one takes a little time to understand the science that Trenberth is discussing, his meaning becomes clear.

If you read the full email, you learn that Trenberth is actually informing fellow climate scientists about a paper he'd recently published, An imperative for climate change planning: tracking Earth's global energy (Trenberth 2009). The paper discusses the planet's energy budget - how much net energy is flowing into our climate and where it's going. It also discusses the systems we have in place to track energy flow in and out of our climate system.

Trenberth states unequivocally that our planet is continually heating due to increasing carbon dioxide. This energy imbalance was very small 40 years ago but has steadily increased to around 0.9 W/m2 over the 2000 to 2005 period, as observed by satellites. Preliminary satellite data indicates the energy imbalance has continued to increase from 2006 to 2008. The net result is that the planet is continuously accumulating heat. Global warming is still happening.

Next, Trenberth wonders with this ever increasing heat, why doesn't surface temperature continuously rise? The standard answer is "natural variability". But such a general answer doesn't explain the actual physical processes involved. If the planet is accumulating heat, the energy must go somewhere. Is it going into melting ice? Is it being sequestered deep in the ocean? Did the 2008 La Nina rearrange the configuration of ocean heat? Is it all of the above? Trenberth wants answers!

So like an obsessive accountant, Trenberth pores over the energy budget, tallying up the joules accumulating in various parts of the climate. A global energy imbalance of 0.9 W/m2 means the planet is accumulating 145 x 1020 joules per year. The following list gives the amount of energy going into various parts of the climate over the 2004 to 2008 period:

Land: 2 x 1020 joules per year

Arctic sea Ice: 1 x 1020 joules per year

Ice sheets: 1.4 x 1020 joules per year

Total land ice: between 2 to 3 x 1020 joules per year

Ocean: between 20 to 95 x 1020 joules per year

Sun: 16 x 1020 joules per year (eg - the sun has been cooling from 2004 to 2008)

These various contributions total between 45 to 115 x 1020 joules per year. This falls well short of the total 145 x 1020 joules per year (although the error bars do overlap). Trenberth expresses frustration that observation systems are inadequate to track the flow of energy. It's not that global warming has stopped. We know global warming has continued because satellites find an energy imbalance. It's that our observation systems need to be more accurate in tracking the energy flows through our climate and closing the energy budget.

So what may be causing the discrepancy? As the ocean heat data only goes to 900 metre depth, Trenberth suggests that perhaps heat is being sequestered below 900 metres. There is support for this idea in a later paper von Schuckmann 2009. This paper uses Argo buoy data to calculate ocean heat down to 2000 metres depth. From 2003 to 2008, the world's oceans have been accumulating heat at a rate of 0.77 W/m2. This higher trend for ocean heat would bring the total energy build-up more in line with satellite measurements of net energy imbalance. However, von Schuckmann's results were published after Trenberth's paper so I look forward to seeing how this plays out in future papers.

So to summarise, Trenberth's email says this:

"The fact is that we can't account for the lack of warming at the moment and it is a travesty that we can't."

After reviewing the discussion in Trenberth 2009, it's apparent that what he meant was this:

"Global warming is still happening - our planet is still accumulating heat. But our observation systems aren't able to comprehensively keep track of where all the energy is going. Consequently, we can't definitively explain why surface temperatures have gone down in the last few years. That's a travesty!"

Skeptics use Trenberth's email to characterise climate scientists as secretive and deceptive. However, when one takes the trouble to acquaint oneself with the science, the opposite becomes apparent. Trenberth outlines his views in a clear, open manner, frankly articulating his frustrations at the limitations of observation systems. Trenberth's opinions didn't need to be illegally stolen and leaked onto the internet. They were already publicly available in the peer reviewed literature - and much less open to misinterpretation than a quote-mined email.

Monckton totally ran with this misrepresentation (among many many others).
http://www.youtube.com/watch?v=ne-X_vFWMlw&feature=player_embedded

A clip of him at Copenhagen berating some activist kids, and using emails and totally inaccurate statements to try and prove a point. I don't think anyone familiar with the science, skeptic or not, would be impressed by his arguments and behaviour.
Highlights:
1. Trenberth email is brought up but cited along the lines "he says the earth has been cooling for past 15 years" which somehow pretends lack of increasing surface temperatures is cooling. Taking a line out of context and then further twisting it is just special.

2. Backs up falsehood number 1 by saying that we have seen "statistically significant cooling over the past 15 years". Apparently the sudoku master has a different way of defining the terms "statistically significant" and "cooling"

3. His continual breach of Godwin's Law.

Back to the Trenberth email. One would have to deliberately seperate the phrase from the rest of the email, from the context in general and to ,perhaps most illogically of all, ignore his recent statements to clarify the issue.

I explain the energy accumulation to others by using the analogy of a small business/shop. I run my store with many items and I take cash only. I know that at the end of the business cycle what my total profit (or loss) has been. But I can't tell which items made a profit, nor how much profit came from each. Its an internal accounting issue, not a bottom line issue.

RSVP, please let's not go there. Accounting has demonstrated its "creativity" and shortcomings throughout the Enron, Worldcom, Tyco, etc, etc, events. All the brilliant economists working wit the Wall Street giants have recently demonstrated a collective failure so spectacular that I don't know how any other science could ever measure up to it. And how many got fired again?

You nicely show that there is no deception on the part of Trenberth but I'm not sure you have either Trenberths position or the science fully explained.

Trenberths paper was published Aug 2009.
The von Schuckmann 2009 paper was published Sept 2009.
The dates on the relevant emails are Oct 2009 such as 1255532032.txt
So when Trenberth wrote that email the data was public. It appears that he is still unconvinced that both sides of the equation were balanced. In fact after others tried to correct his comment he followed with this
"How come you do not agree with a statement that says we are no where close to knowing where energy is going or whether clouds are changing to make the planet brighter. We are not close to balancing the energy budget." (dated Oct 14, 2009)

There is a further issue John. Trenberth states that from 1993 to 2003 the energy imbalance is perfectly accounted for based on the 'conventional' understanding of the system. So any changes you wish to introduce after 2003 (such as sequestering to the deep ocean) could not be applied to the previous decade. In other words a significant global energy transport system would have to be 'switched on' in 2003 in order for the sums to add up over all of the recent past. Does this seem reasonable?
It seems you are blunting Occams Razor here.

@RSVP:
If you think the estimates are wrong, please indicate how. You should also explain how deep ocean heat, which is directly measurable, is _technically_ analogous to dark matter, which isn't. Otherwise, may I suggest that at WUWT you find a better audience for that kind of commentary.

The situation is that Trenberth has been misrepresented and misunderstood, and this post sets it straight. I think this should also be seen in the light of discrepancy between model forecasts and actual temperature development during the last decade - the basic physics does not seem to be wrong, but the modeling clearly is.

Your explanation of the email relies upon what is set up in " An imperative for climate change planning: tracking Earth's global energy (Trenberth 2009)". In this report Trenberth clearly states what is "Given"...

"Given that there is continual heating of the planet, referred to as radiative forcing, by accelerating increases of carbon dioxide (Figure 1) and other greenhouses due to human activities, why is the temperature not continuing to go up?"

..and you apparently accept this "Given" in your analysis.

"Trenberth states unequivocally that our planet is continually heating due to increasing carbon dioxide."

Trenberth claims in his email that the earth based systems are inadequate to account for the imbalance based upon this "Given". Being a skeptic, that makes me question the adequacy of the satellite system of measuring radiation in and out of the atmosphere.

Trenberth obviously believes that this satellite data is without any substantial systematic error and the probable error of the data can be trusted with no substantial shift in actual data values due to said lack of systematic error. If not, then there is no way he could claim that the earth based systems used are inadequate.

This logic reminds me of religious fanatics who can only cite the Bible as the way to prove the Bible is without error.

I will now direct my attention to understanding the satellite measurements. Thank you for your article.

00

Response: The point of this article is to clarify Trenberth's views which have been misrepresented. Just because Trenberth says the planet is still heating due to CO2 doesn't make it so. But it does establish that Trenberth believes it so - and thus the characterisation that Trenberth is saying global warming has stopped is erroneous.

MACaTAC wrote "
Trenberth claims in his email that the earth based systems are inadequate to account for the imbalance based upon this "Given". Being a skeptic, that makes me question the adequacy of the satellite system of measuring radiation in and out of the atmosphere."

That is not what Trenberth claimed. Instead he claimed that the scientists' understanding of the Earth's energy systems is insufficient to fully account for the short term and detailed fluctuations in the energy budget. The observations of energy in and out of the Earth are solid.

My understanding of trenberths paper is that he identifies error in the calculation of the energy balance of the planet. As he says 'Where has the energy gone?"
He begins the discussion about were this error may occur identifying weakness in our measurement of many of the variables in the system as well as our lack of understanding on some of the systems (such as clouds).

One thing he does is to constrain some of the possible answers to this conundrum using sea level rise. He points out that if the energy has gone into sea ice, land ice, deep oceans or land this would have had different affects on sea level. By this method he is able to rule out most of the possible options as to where the energy has gone.

My understanding is there are only two possible options. Changes is cloud cover, although no mechanism is known and measurements are poor. This only exists as an option because of the poor understanding.
The other mechanism is, as John pointed out, into the deep sea but this is speculative, has no known mechanism and requires re-jigging of other factors in the energy budget system in order to also satisfy the observed sea level rises.

I think what Trenberth is identifying here is not weakness in models, not just weakness in our observations but also a small hole in the basic physics of the system.

@15
I don't think we should start looking for small holes in the basic physics before we have checked out all our applications of it. To me, one of the basic problems with the budgeting is the assumptions about the radiative imbalance. As Trenberth implies in one of the emails (but not in the paper?), this is by no means constant, even though we may have rather precise estimates of the average (expectation) value (0.9 W/m2, 90% CI 0.4-1.4). Maybe it should be modeled as a stochastic variable, something like a multi-dimensional pseudo-random walk.

There may also be too simplistic assumptions about the interplay between GHG forcing and water vapor.

We may have small holes in the basic physics too, right now perhaps most likely in the areas of magnetism/cosmic rays vs cloud formation. But several studies indicate that this is unlikely to have any major influence on the big picture we are discussing. Where we do not attempt to model cloud formation with any great precision, but rather work out from the observed radiation balance.

It's my understanding that it's not just cosmic rays vs clouds that we don't understand but many more aspects of clouds such as changes in precipitation rates and cloud life that we don't understand. Look at the error bars in fig4 on trenberths paper.

I don't think we really disagree that much - to me it seems more a question of wording. I agree with you about the lack of knowledge you mention, to me it just seems more on an applied rather than basic level. My impression is that the basic governing equations for the situation can be set up, but we are not able to find satisfactory solutions to them. And, for instance, knowing the details of how a system is chaotic and therefore in some respects not completely predictable, is a piece of physical knowledge for me, not a lack of it.

you appear to be entering Rumsfeld territory here. Known unknowns and unknown unknowns. I can accept a known unknown can be constrained within the system but with some of the forcing they are approaching unknown unknowns. Take cloud as an example again. These impact on energy transport in multiple ways having both + and - affects. It seems that just what the overall nett affect of changes in cloud cover, or the processes that my drive that are completely unknown. As you say I don't necessarily make the distinction between basic and applied but if I had to I'd put this in the basic camp.

HumanityRules, I think one needs to be a little more careful with “knowns” and “unknowns” and not to fall into the trap of mistaking uncertainties in sub-levels of phenomena with uncertainties in the phenomena, themselves.

There’s quite a lot we know pretty well about the cosmic ray flux (CRF) and its effects on surface temperature:

1. We know, for example, that any secular trend in the CRF during the period in which it has been monitored in detail (since late 1950’s) can have made no contribution to the very marked warming in the last 30-odd years. If anything, any putative CRF effect should have caused a slight cooling.

2. We know that the CRF doesn’t seem significantly to affect low level clouds in the way proposed by the practitioners of this notion. An apparent correlation was reported for solar cycle 22. This relationship broke down through solar cycle 23. Analysis of the relationships between the solar cycle and the apparent cloud effect that was observed through solar cycle 22 indicates that is the solar irradiance component of the solar cycle that might have influenced low level clouds through cycle 22.

3. We know that there is no evidence for a CRF effect on climate during the past 1000 years. The CRF variation reconstructed from cosmogenic isotope (14C) formation leads the temperature variation through the MWP period. In other words it can’t have made a significant contribution. Likewise, the surface temperature variation through the LIA is fully understandable in terms of solar irradiance variation and other rather well characterised forcings (volcanic and greenhouse gas variations).

No doubt there is uncertainty about CRF effects on atmospheric aerosol formation. However this sub-level of uncertainty doesn’t negate the broader likelihood that CRF variation hasn’t made any contribution to the marked warming of the last 30-odd years. In a similar vein, the uncertainties of how exactly how the sea level rise of the last 5 years is partitioned into its thermal and mass components doesn’t negate the broader certainty that the sea levels have continued to rise during this period.

Similar analysis applies to clouds. While the earth’s surface has warmed considerably during the past century, there’s no evidence for a significant contribution from cloud cover variation. If clouds produced a negative feedback one wonders where this is! Much of our understanding of climate sensitivity (the earth surface temperature response to enhanced radiative forcing) is based on empirical relationships between historical temperatures and greenhouse gas levels. These implicitly incorporate any cloud feedbacks (and other feedbacks like fast water vapour and albedo effects).

Of course if we want to understand everything in a great amount of detail, we want to have a handle on all the sub-components of the phenomenon whose contributions sum to the phenomenon itself. This is what Trenberth is attempting to establish. Unfortunately the measurements are not sufficient to do this in detail for very short time periods. For example the CERES data that yielded radiative flux at the top of the atmosphere at high precision is only available through Feb 2005. There is still some uncertainty in the ocean heat measures, particulalry at depth.

As Trenberth states in the article in which he discusses the uncertainties in ascribing precise contributions to surface temperature variation and heat flow/distribution in the last few years, and suggests a number of possible contributions:

”…Perhaps all these things are going on. But surely we have an adequate system to track whether this is the case or not, do we not? Well it seems that the answer is no, we do not. But we should!”

That’s what Trenberth is on about. We certainly don’t cast doubt on our understanding of the physics of a system until we have sufficient confidence in the measurements that would indicate that there is something to concern ourselves with.

The CERN experiment on cosmic rays is anything but conclusive so far. They are struggling to prevent interactions with the chamber wall from completely ruining the experiment. In my opinion, it does not bode well for the hypothesis in the real world, where CCN are found in the millions per liter of air, whether over land or water. And over the ocean these CCN include lots of ions.

Philippe, I agree...in my opinion the CERN experiment will never be conclusive about any putative effect of CRF variation on clouds, let alone climate. It's simply not an experiment that can yield information on this subject.

The experiment will no doubt yield useful physicochemical information on aerosol particle nucleation by gamma rays under controlled conditions in a particle chamber, and its response to variation in the composition of atmospheric mimetics. Also, in my opinion, the main proponent of the CERN experiment has misrepresented the science on contributions to historical temperature variation, as a way of "beefing up" the justification for the experiment [*].

My question is: why Trenberth did not put the same question about the accuracy of surface data when the temperasture increase appeared to be unstoppable?
It does not appear to me 'a clear, open, manner' to manage the issue.

John Cook at 2009-12-12 23:44 PM wrote: "Trenberth states unequivocally that our planet is continually heating due to increasing carbon dioxide. This energy imbalance was very small 40 years ago but has steadily increased to around 0.9 W/m2 over the 2000 to 2005 period, as observed by satellites"

No, he states nothing like that, unequivocally or otherwise. What Trenberth actually says is this:

"There is a TOA imbalance of 6.4 W/m^2 from
CERES data and this is outside of the realm of current
estimates of global imbalances (Willis et al. 2004;
Hansen et al. 2005; Huang 2006) that are expected
from observed increases in carbon dioxide and other
greenhouse gases in the atmosphere. The TOA energy
imbalance can probably be most accurately determined
from climate models and is estimated to be 0.85 ±
0.15 W/m^2"

He simply sets the satellite-measured radiative energy balance of 6.4 W/m^2 at the top of the atmosphere to the entirely different value of 0.85 ± 0.15 W/m^2 based on climate models. It is equivalent to the proposition that satellite measurements are useless in this respect, so one has no choice but to verify climate model predictions using data derived from the model itself.

In this case however, one can NOT say that the value of 0.9 W/m^2 is "observed by satellites". Or can, provided true and false statements have equal right to be uttered.

Given that there is continual heating of the planet, referred to as radiative forcing, by accelerating increases of carbon dioxide (Figure 1) and other greenhouses due to human activities, why is the temperature not continuing to go up? The stock answer is that natural variability plays a key role [1] and there was a major La Nin˜ a event early in 2008 that led to the month of January having the lowest anomaly in global temperature since 2000. While this is true, it is an incomplete explanation.

And a few paragraphs further along:

Given that global warming is unequivocally happening [2] and there has so far been a failure to outline, let alone implement, global plans to mitigate the warming, then adapting to the climate change is an imperative.

The broader point I was trying to make is that Trenberth's out-of-context quote was being used to portray him as privately not believing global warming is happening. This is decidedly not the case as is clearly communicated in the peer review literature.

"In general, heat storage, solar insolation, and TOA SW reflected flux dominate the systematic errors. Almost all systematic errors appear as planetary heating in the global net balance. Some of the errors like diurnal sampling biases await final confirmation using combined global 1030 Terra, 130 Aqua, as well as 3-hourly and 1-hourly geostationary data sources for SW fluxes, and GERB 30-minute broadband data from METEOSAT for SW and LW flux diurnal cycles.

When all errors are combined, CERES Terra SRBAVG Edition2 non-GEO global Net flux is 6.9 Wm-2 versus a predicted range of 1.3 to 6.1 Wm-2. The ERBE-like global net flux is 3.8 Wm-2 versus a predicted range of -3.1 to 1.7 Wm-2. The less accurate ERBE-like global net flux comes closer to zero. The reason, however, is not more accurate TOA fluxes, but fortuitous cancellation of errors of opposite sign. The ultimate goal is of course to get the right answer for the right physical reasons. For example, the improved CERES angular dependence models improve the accuracy of the equator to pole gradient of reflected SW fluxes, especially in polar regions.

Now why do I not feel confident about quoted figures for TOA radiation budgets??

John, you miss the point. It's rather irrelevant if Trenberth is believing in "global warming" or not. To be sure, he apparently does not believe in the possibility of radiation budget imbalances on the order of 6.4 W/m^2 like you do. For this is what's "observed by satellites".

But his alternative, "the TOA energy imbalance can probably be most accurately determined from climate models" is in no way better. It implies "correcting" the (mis)measured imbalance according to a model, then certifying the model by the imbalance found. Bit circular.

It turns out however, that TOA energy imbalance can be and is measured after all. By Argo floats, not satellites.

Indirectly, of course. It's elementary thermodynamics. Global OHC (Ocean Heat Content) "anomaly" should be nearly proportional to the time integral of the "TOA energy imbalance" (integrating incoming and outgoing flux difference for an epoch on the surface of the globe, that is). Both specific heat of water and its quantity on Earth are enormous.

http://www.nodc.noaa.gov/OC5/3M_HEAT_CONTENT/

You can see on the NODC site that OHC is flat for the last five years. It also happens to be the time interval we have reliable data. For Argo coverage only reached a reasonable level at the end of 2003 (and was completed by 2007). Earlier "measurements" of OHC are guesswork.

"it is important that the trends of water vapor shown by the NCEP data for the middle and upper troposphere should not be "written off" simply on the basis that they are not supported by climate models"

That's it.

00

Response: The planet's energy imbalance obviously isn't 6.4 W/m2 - it's more of the order of around 0.85 W/m2. Satellite measurements have low accuracy but high precision. In other words, they display a high uncertainty in the absolute value of the radiation budget but stronger precision in year to year variability. So the satellite data is constrained - either by climate models or by ocean heat data (or both) in order to calculate the absolute energy imbalance.

#27...surely in order for the ocean depths to warm, the surface water must do so first and then be mixed with deeper layers. This surface warming should be apparent unless you are saying the heat is transported more or less instantaneously (in climate terms)??

But there is one thing I firmly believe in. That's there is an ultimate reality. And there are also propositions that match this reality and if they do, they are called true statements. In other words truth does exist. Not just in our minds or discussions, but on its own right.

This is why false statements like "the planet is continuously accumulating heat" "as observed by satellites" are annoying.

Let's be more specific. Satellite OLR (Outgoing Longwave Radiation) measurements are fairly reliable. They may have a large systematic error, that is, they are inaccurate in your terms, but they are precise indeed in the sense that random errors are limited. So they are good for determining trends, but nothing else.

As derived from various satellite data there is a consistent 0.12 W/m^2 yearly decrease in OLR since 2003.

In other words the effective temperature of Earth as seen from the outside has dropped by about 0.15°C during this six year period.

Of course it does not mean much and it is especially loosely related to average surface temperature.

However, effective temperature itself is a well-defined concept, even if it is too abstract for most practical purposes (it is the temperature of a uniformly heated black body having the same outgoing thermal radiation energy flux as the object considered).

The absolute value is somewhere between -15°C and -19°C, depending on the season, the particular satellite set used and method calculated.

On the other hand ASR (Absorbed Shortwave Radiation) as measured by satellites is not even precise. The reason is that reflected sunlight has a very complex spectral, spatiotemporal and angular distribution, and both satellite coverage and spectral resolution of measurement are insufficient to capture it precisely.

If we knew both solar constant variations and outgoing radiation from earth for the entire spectrum and all spatial directions with sufficient precision, it would be easy to calculate the energy balance. But as for now, the noise, mainly from spatiotemporal and angular undersampling at higher frequencies is so huge, that the energy balance of earth is not measured this way in any reasonable sense.

If anything can be said about the short wave reflectance history of earth, it is that it's fairly stable in this period (within measurement error bounds). At the same time solar constant is slightly decreasing due to an extended low in solar cycle, so one can not say that the rate earth gained or lost energy has changed significantly.

Of course it does not say anything about the possible initial offset between OLR and ASR at TOA, but that's exactly my point. The energy imbalance is NOT measured by satellites.

Climate model predictions are also unfeasible for calibrating offset errors in energy balance measurements. The whole point of measuring imbalance is to verify models in the first place, isn't it?

We are left with OHC, can forget both satellites and models.

Here is a preprint of the von Schuckmann paper:
http://www.euro-argo.eu/content/download/49437/368494/file/VonSchukmann_et_al_2009_inpress.pdf

I have two problems with it.

1. Why could not he give OHC estimates for the 0-700 m subset as well?

This way his results would be directly comparable to NODC estimates. As it is, one wonders what physical mechanism can transfer so much heat below 700 meters without even touching the strata in between? Weird.

2. I don't like graphs where all the error bars are of exactly the same size.

Number of Argo floats grew fourfold during the period 2003-2007. Coverage have had also improved. It would imply error bars shrinking approximately half their original size. However, the vertical line segments on the figure look more like uniform ornaments.

Schuckmann does not elaborate much on these problems in the text either.

It's also remarkable that until recently in parts of the ocean where stratification, hence density difference between the surface and 2000 m depth level was too large, Argo floats could not make profiling of the entire water column, so they were programmed to go no deeper than 1000 meters (otherwise they could not return to the surface). New models can perform better on a slightly increased cost.

What it actually means is that 0-2000 m OHC estimate is considerably less accurate for this time period than 0-700 m estimates.

There is also an aging problem with the pressure sensors. An ever increasing number of floats report negative pressure at the surface, up to 30% of them by now.

Schuckmann also fails to mention these arcane details.

You can read more about float problems in Argonautics #10 (July 2008), pp 7.

Profiling to 2000 m Anywhere in the World Ocean: Advances with APEX Floats
Stephen C. Riser, University of Washington
http://www.argo.ucsd.edu/Argonautics10.pdf

One more thing. If you have a closer look at the figure (Global Ocean Heat Storage 0-2000 m) you have shown us from von Schuckmann 2009, you may notice a considerable jump at the turn of 2006/2007.

In just two months OHC went up by 8x10^7 J/m^2. It is huge. It requires some 15 W/m^2 surplus heat flux for an extended period (9 weeks). Even taking into account the error bars, it's 15 ± 6.5 W/m^2. It is 6% of the heat flux coming from the sun to the surface. If this much heat is transferred to the ocean, it would cool down the ENTIRE atmosphere by 8°C. In midwinter. And he says most of the marine heat gain occurred in the North Atlantic. If I had three legs it would not pass unnoticed.

This article seems like a great candidate for a revisit after Solomon's article on vanished vapor. A significant part of Trenberth's gap is seemingly plugged, if Solomon's results stand it'll be a great improvement in our understanding of variability.

Thank you very much for the excellent explanation.
One point still puzzles me, though, perhaps because I'm Italian: the word 'travesty'. According to my good old Oxford Dictionary it means 'a description that intentionally misrepresents the original e.g. burlesque poem etc.' etymology being the Italian verb travestire = disguise. It somehow conveys the impression that the whole thing is a farce, a dress up, an attempt to deceive.
I understand in private informal correspondence one doesn't care much about wording, but, why didn't he use pity or shame or bad luck?

it is also expedient to reconsider arbitrary data homogenization techniques used in retrospective "adjustment" of historical radiosonde temperature & humidity measurements.

Just documented instrumentation changes should be used and only after experimental recalibration of the actual devices used.

There are numerous abrupt downward shifts identified in the record. There is an extensive literature identifying them as artifacts. Having "corrected" the record by subtracting a step-function constructed this way, the overall downward trend vanishes.

After the Solomon paper this practice is untenable.

What if it's not just "natural variation" but the very way the climate system reconfigures itself to accommodate to increased CO2 levels?

In a nonlinear system "feedback" can work in tricky ways. It can be positive on the "micro" level while occasional abrupt topological shifts can make the overall behavior well regulated within tight bounds, i.e. bring the state back to "normal".

Let me clarify the idea through an example. Consider a pot of boiling water heated from below. As anyone knows, there are bubbles forming in the liquid and rising to the surface. Now, bubble formation is a tricky process, for each bubble should start tiny with a huge curvature on its outer surface, hence large negative surface tension. It throttles evaporation for a while, but as soon as the bubble gets bigger, this effect diminishes. We have a positive feedback. With very clean water free of "seeds" (like motes or air bubbles), it can get rather explosive. Just put clean water into the microwave, boil it for a while, let it cool, then re-boil. Don't use a bottle with a tight neck, it could actually blow up. And be prepared to clean up the mess.

Anyway, in a normal pot of boiling water bubbles regularly end up on the surface and burst, releasing water vapor to the environment. It is a highly chaotic process, but the overall vapor contents of the pot is regulated, in spite of the positive feedback in bubble formation. Temperature is also constant with only slight local and temporal variations.

One can see, the negative feedback works on a higher level and requires occasional reconfiguration of topology (bubble burst).

If vapor contents of the pot were measured as a time series, then sudden drops associated with these topological changes removed from the record, one would fancy an ever increasing amount of steam in the pot.

Putting some substance on the surface of water like oil would not make much difference. Of course it could "trap" steam for a while. Individual bubbles could get a little bit larger before bursting. But neither the temperature, nor the volume integrated steam contents of the pot would change.

The dynamics of "water vapor feedback" to "carbon dioxide forcing" can be just like that.

Hence the single station measurement is equivalent to a local measurement in the pot; it must be corrected with a nearby stations if for any reson locally there has been an unjustified jump. If the jump is real, it shows up in nearby stations also.
It's so true that there are non climatic jumps that the corrections average to zero globally. As always, people like to discredit stations measurements with no real reason, just becasue it's "usefull to the cause".

I have seen the comments in skeptical forums over and over regarding lack of recent ocean heating as measured by Argo data. The problem is that I never see anyone try to reconcile the data with the 2009 paper cited above, or with SLR as Trenberth tried to do.

Taking a reasonable time horizon, and realizing SLR measurements by satellites show some cyclical nature due to El Nino (fast SLR) and La Nina (slow SLR), I see that sea level from the 1998 El Nino to the current El Nino is about 30 mm, quite consistent with the long term trend in SLR. The question remains how much of the SLR is coming from ocean heating and how much from ice sheet melt?

If you are correct, and ocean heating has stopped, then that would mean ice sheet melt has accelerated to an almost impossibly high rate to account for the 30 mm in SLR over the last ten years. But we have some indications of ice sheet melt from GRACE data, and the high ice sheet melts required under the hypothesis of level OHC are not confirmed! Clearly there is still significant heat buildup in the ocean, as Trenberth reports.

Why is it that the skeptics claim both low ice sheet melts and level OHC. These two extremes taken together contradict observed SLR, and contradict GRACE data. All the information points to a problem with extrapolating the first Argo data reports to the entire ocean. I think that the estimates of ocean heat buildup must be consistent with SLR and GRACE, and be particularly wary of using OHC or SLR data that ends in a La Nina year (2008), like the skeptics do, when they quote 2004 to 2008. At least use three or four ENSO cycles to reduce the impact of ENSO on these data sets.

The use of SLR data to "validate" the Schuckmann conclusions is, in my view, not a robust argument. The long-term tidal guage data shows a (remarkably) constant gradient trend throughout the 20th century, despite the significant variation in both average surface temperature and estimates of OHC.
This suggests that the prediction of OHC from SLR data is mathematically ill-conditioned.
Given the now critical importance of the deep OHC data in underpinning the basic foundations of AGW, I would really like to see a full regional reconciliation of the Schuckmann findings with the more certain 0-700m data, and a realistic estimate of the uncertainty associated with the deep temperature measurements. I am honestly surprised that he did not include this analysis in the paper to add credibility.

Zinfan94,
You wrote:
"Why is it that the skeptics claim both low ice sheet melts and level OHC. These two extremes taken together contradict observed SLR, and contradict GRACE data."

Further to my post above, you really should read Cazenave et al 2008, which is the consensus science view on reconciliation of TG data, altimetry, ocean mass balance (including GRACE data) and ARGO data. It calculates steric sea level rise (thermal plus salinity) from 2003 to 2008 from Altimetry minus mass balance (two different ways) as 0.31mm/year, and independently calculates the value by thermal expansion from ARGO data as 0.37mm/year. This uses 0-900m ARGO data. It concludes:-
QUOTE The steric sea level estimated from the difference between altimetric (total) sea level and ocean mass displays increase over 2003–2006 and decrease since 2006. On average over the 5 year period (2003–2008), the steric contribution has been small (on the order of 0.3+/−0.15 mm/yr), confirming recent Argo results (this study and Willis et al., 2008).ENDQUOTE

You will note that there is no room in this analysis for any additional deep OHC, quite the contrary. Either Schuckmann or Cazenave has some further explaining to do in order to reconcile these two papers.

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